Photomechanical printing.



No. 807,272. PATENTED DEC. 12, 1905.

J. W. I PPERS. PHOTOMEUHANIGAL PRINTING.

APPLICATION FILED JULY 14,1906.

' UNITED STATES PATENT OFFICE.

JOHN W. IPPERS, OF NEW YORK, N. Y., ASSIGNOR TO ALBERT HENRY WALKER, TRUSTEE, OF NEW YORK, N. Y.

PHOTOMECHANICAL PRINTING.

Specification of Letters Patent.

Patented Dec. 12, 1905.

Application filed July 14, 1905. Serial No. 269,593-

, To all whom it may concern:

Be it known that I, JOHN W. IPPERS, formerly a subject of the German Emperor, but now a citizen of the United States, and a resident of the city of New York, and State of New York, have invented a certain new and useful Improvement in Photomechanical Printing, of which the following description and claims constitute the specification.

The primary object of my invention is to prepare the periphery of a metal roller for continuously printing lines or graduated or ungraduated surfaces on cloth or paper or other suitable material.

The nature of my invention consists in mak ing upon a stone slab or a metal platea printing-surface capable of printing one copy of a desired design or picture and in applying transfer-ink to that stone slab or metal plate and in transferring ink from that slab or plate by means of atransfer-roller to the periphery terial constitutes the base of the design or picture which results from the process.

The merit of my invention includes the fact that it results in the production of a printingsurface which can be used for continuouslyrepeated printing of the design thereon, and the nature of that merit and the process by which itis attained are illustrated by the accompanying drawings and the following explanation.

Figure 1 of the drawings represents a transparent glass plate which has received an application of opaque ink, paint, varnish, or other adhesive substance on the longitudinal stripes, which are shown in black in that figure. Fig. 2 is a view of alithographic stone which has received printing-surfaces on the black longitudinal stripes of that figure. Fig. 3 is a "iew of a transfer-roller which has received deposits of transfer-ink from the stone slab of Fig. 2 on the black zones extending entirely around that roller. Fig. 4: is a view of a copper roller which has received intaglioprinting surfaces on the black zones which extend around that roller. Fig.5 is a view of a strip of cloth of indefinite length which has received deposits of printing color on the black stripes shown in that figure.

The transparent glass plate of Fig. 1 is made with a brush or is made photographically or in any other way that will result in making opaque those surfaces which are in black in that figure.

The lithographic stone of Fig. 2 is prepared as follows after it has been given a level surface and a polished face: I make a sensitizing solution by beating the whites of three eggs in four and one-half ounces of water and by adding thereto three drams of bichromate of am-' monia dissolved in four and one-half ounces of water and by adding fifteen drops of liquid ammonia to the whole, and I keep and use this sensitizing solution in a dark room. I then warm the stone by pouring hot water over it, and then I flow the sensitizing solution over it and dry thereon'the film thus deposited. Thereupon I clamp the transparent glass plate of Fig. 1 down upon the sensitized stone and in close contact therewith. Then I expose the sensitized stone to light through the transparent glass plate, about one minute, if the light be directsunlight, or about eight minutes, if it be clear north daylight. I next remove the glass plate from the stone in a dark room and at once roll transfer-ink evenly over the entire sensitized surface of the stone. I then flow cold water over that inked surface and wash away with a cotton ball in the water all the ink which was deposited on those areas of the stone which were under the opaque stripes of the glass plate during the exposure; but that washing does not disturb the ink on those surfaces of the stone which were under the transparent stripes of the glass plate during that time. Thereupon I dust powdered rosin over the stone, and it is taken by the inked areas of the stone, but not by those areas from which the ink was washed away. I next apply with a brush to the stone a solution of two ounces of gum-arabic and twenty-five drops of nitric acid in six ounces of water, which solution etches the uninked areas of the stone, and after that etching I wash away the surplus solution with water. Thereupon I apply to the stone a solution of two ounces of gum-arahic and six ounces of water, and that solution adheres to the uninked areas of the stone, but does not adhere to its inked areas. I then apply to the stone a mixture'of equal parts of asphalt, varnish, and turpentine, which mixture removes the ink from the stone, but does not disturb the gum-arabic thereon. I then apply water with a sponge to the stone, and thus remove the gum, but do not disturb the asphalt. At this stage of the process those areas of the stone which were under the transparent stripes of the glass plate during the exposure are covered with asphalt, while those areas are naked which were under the opaque strips of the glass plate at that time. applied to the stone and is absorbed by its naked areas, but is repelled by those areas which are covered with asphalt. Transferink is then applied to the stone and is repelled by the watered areas thereof, while it is taken by the areas which are covered with asphalt.

The transfer-roller of Fig. 3 consists of a roller of soft rubber having a metal shaft in its center and a coat on its periphery made by depositing and drying thereon a solution of one ounce of copper gelatin and one-half an ounce of kremser white and one-quarter ounce of light syrup and twenty-five drops of carbolic acid in twenty-two ounces of water. This solution is made by putting its ingredi ents in a pot, and by putting that pot in a larger pot containing water and by heating the contents to a degree somewhat below the boiling-point of water. This solution is applied'to the rubber roller with a'fine brush, and it is driedwhile the roller stands on its end in a warm and dustless room. I specify u.

copper gelatin for my present solutlon because it is softer and more elastic than silver gelatin or golden gelatin, which three grades are so called because they are, sold in packages having labels colored like copper and silver and gold, respectively; but either silver gelatin or golden gelatin can be used in my present solution if thereis added thereto enough glycerin to produce the proper softness and elasticity.

The transfer-ink which I apply to the prepared stone and transfer thence to the transfer-roller andthence to the copper roller is composed of one pound of rosin, one pound of asphaltum, one pound of mastic, half a pound of beeswax, and three ounces of mutton tallow melted together and then mixed with twice its quantity of the crayon-ink of commerce, which latter is composed of cooked linseed-oil and lampblack without any fat.

The transfer of ink from the inked stone of Fig. 2 to the transfer-roller of Fig. 3 and thence to the copper roller ofFig. 4 is accomplished by rolling the transfer-roller over the stone slab and by contemporaneously or afterward rolling the transfer-roller in contact with the copper roller when the shafts of the two are exactly parallel to each other. The transfer cannot be made directly from the stone slab to the copper roller, because the surfaces of both are hard and because Thereupon water is.

good ink-transfers cannot be made between two hard surfaces in contact. At this stage of the process the copper roller of Fig. 4 has received deposits of ink on the areas which are white in that figure. Having reached this stage of the process I proceed as follows:

I change the ink into an enamel by means of areas of that surface without adhering to the naked areas thereof. Then [heat the copper to a temperature high enough to melt the enameling-powder into the ink to whichithas adhered. This heating results in changing the ink on the surface of the copper roller into an enamel, and that enamel will protect those areas of the copper roller covered thereby from the eating of the etching liquid, which is subsequently applied to the copper roller. I next protect the interior of the roller, if it is hollow, and also its ends with asphalt-varnish from the action of the etching liquid, which I next apply to the periphery of the roller. 1 make that application by simply causing the roller to rotate above a pan containing the etching liquid and with all portions of the periphery of the roller successively passing through the etching liquid in the pan as the roller is rotated. That etching liquid, which may bechlorid of iron, eats into the naked portions of the periphery of the copper roller, while not affecting those portions of that periphery which are covered by the enamel. cause the etching liquid to do its etching work for a greater or less length of time. according as I intend to etch more or less deeply into the periphery of the copper roller, and thus give more or less depression to its etched areas. After the periphery of the copper roller has been etched I wash it with water to remove the etching solution, and then I remove the enamel from its relief areas with turpentine. The periphery of the copper roller having been thus provided with depressed or intaglio printing-surfaces,the roller is used in a printing-machine as if it had received those surfaces from the hands of an engraver. That use consists in applying ink or color to the periphery of the roller and in scraping or wiping it away'from therelief surfaces thereof and in drawing a strip of cloth between it and a plain roller opposite thereto, and in transferring ink or color from the depressed surfaces of the roller to that strip of cloth.

The particular program illustrated in the drawings has thus far been the subject of this description. That program is confined to intaglio printing of flat masses in one'color on strips of cloth; but this invention is not con- IIO fined to intaglio printing, for it includes relief printing also, and it is not confined to printing flat masses. for it includes also printing in unbroken lines and printing graduated pictures of natural or artificial subjects.

A stone slab is said in the foregoing description to be the foundation of the photographic picture printed thereon through the transparent plate of Fig. 1; but a copper plate may also be that foundation and may receive its photographic picture in any of the ways in which copper plates have heretofore been thus provided, and having received that picture a copper plate may be etched in any known way, and having been thus etched it may receive transferrink and may transfer that ink to the rubber roller of Fig. 4 and thence to the copper roller of Fig. 5.

A copper roller is said in the description to be the printing instrumentality which is made and used in my process; but such aroller may be made of aluminium, zinc, or other metal and may be prepared and used as set forth in this specification, except that different metals are best etched with different etching liquids,

and such a roller, of whatever metal, should be well polished for intaglio printing before the ink is applied thereto from the gelatin plate, though for relief printing its periphery may be finely roughened instead of being polished before it is inked and etched.

Relief printing according to my present invention differs from the'foregoing description of intaglio printing in that the transparr ent glass plate of Fig. 1 would be striped like Fig. 2, and in that the stone slab of Fig. 2 would be striped like Fig. 1, and in that the transferroller of Fig. 3 would be striped like Fig. A, and in that the copper roller of Fig. 4 would have its black zones orbands in relief instead of in depression, and in that the depressed surfaces of that roller would be deeper than when they are the printingsurfaces thereof, and in that ink would be applied to the relief surfaces only of the roller and be transferred thence to the strip of Fig. 5, which would generally be paper instead of cloth.

Printing unbroken lines according to my present invention differs from the foregoing description of printing in flat masses in that the original design or picture of Fig. 1 would consist of unbroken lines instead of flat masses of opaque areas.

Printing graduated surfaces according to my present invention differs from the fore going description of printing in flat masses in that the inked surfaces of the stone or plate of Fig. 2 would receive separate and minute deposits of transfer-ink of varying extents and frequencies instead of continuous masses of such deposits. The deposits of ink on the inked surfaces of the stone or plate of Fig. 2 can be constituted of such separate and minute bodies in either of several diiferent ways, of which the use of a half-tone transparent photograph instead of the transparent glass plate of Fig. 1 is an example. The exposure of the sensitized stone slab or metal plate of Fig. 2 to light passing through a transparent halftone photograph would ultimately result in deposits of separate and minute bodies of transfer-ink on the printing-surfaces of that slab or plate, and those deposits not being separately recognized by the naked eye would have the visual effect of structureless and graduated gray. That graduated gray would be transferred from the stone or plate of Fig. 2 to the transfer-roller of Fig. 3 and thence to the copper roller of Fig. land would finally be propagated upon the printed strip of Fig. 5.

I claim as my invention 1. I The following process of photomechanical printing: making a sensitive surface on a stone slab or metal plate: exposing that sensitive surface to light, through a sheet which is partly transparent and partly opaque: developing that exposed surface into a condition in which some of its areas will receive ink, while some of its areas remain free from ink: applying ink to those areas which are to receive it: transferring ink from that inked surface, to the periphery of a soft and receptive transfer-roller: transferring 'ink from that periphery, to the periphery of a metal roller: etching away the uninked parts of that periphery: applying printing ink or color to the printing parts thus produced on that periphery: and transferring ink or-color from those printing parts, to the surface of whatever cloth or other material constitutes the'base of the picture or other print which results from the process; all substantially as described.

2. The following process in photomechanical printing: making a sensitive surface on a stone slab or metal plate: exposing that sensitive surface to light, through a sheet which is partly transparent and partly opaque: developing that exposed surface into a condition in which some of its areas will receive ink, while some. of its areas remain free from ink: applying ink to those areas which are to receive it: transferring ink from that inked surface, to the periphery of a soft and receptive transfer-roller: transferring ink from that periphery, to the periphery of a metal roller: and etching away the uninked parts of that periphery; all substantially as described.

JOHN W. IPPERS.

Witnesses:

ALBERT H. WALKER, OLIVER D. WOODRUFF.

ICC

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